customize HandlePanic per executor

unbounded_executor.go

@@ -7,17 +7,13 @@ import (
 	"runtime/debug"
 	"sync"
 	"time"
+	"reflect"
 )
 
-// LogInfo logs informational message, for example
-// which goroutine is still alive preventing the executor shutdown
-var LogInfo = func(event string, properties ...interface{}) {
-}
-
 // HandlePanic logs goroutine panic by default
-var HandlePanic = func(recovered interface{}, file string, line int) {
-	fmt.Println(fmt.Sprintf("paniced: %v", recovered))
-	debug.PrintStack()
+var HandlePanic = func(recovered interface{}, file string, line int, funcName string) {
+	ErrorLogger.Println(fmt.Sprintf("%s defined at %s:%v panic: %v", funcName, file, line, recovered))
+	ErrorLogger.Println(string(debug.Stack()))
 }
 
 // StopSignal will not be recovered, will propagate to upper level goroutine
@@ -30,6 +26,7 @@ type UnboundedExecutor struct {
 	cancel                context.CancelFunc
 	activeGoroutinesMutex *sync.Mutex
 	activeGoroutines      map[string]int
+	HandlePanic           func(recovered interface{}, file string, line int, funcName string)
 }
 
 // GlobalUnboundedExecutor has the life cycle of the program itself
@@ -40,6 +37,7 @@ var GlobalUnboundedExecutor = NewUnboundedExecutor()
 
 // NewUnboundedExecutor creates a new UnboundedExecutor,
 // UnboundedExecutor can not be created by &UnboundedExecutor{}
+// HandlePanic can be set with a callback to override global HandlePanic
 func NewUnboundedExecutor() *UnboundedExecutor {
 	ctx, cancel := context.WithCancel(context.TODO())
 	return &UnboundedExecutor{
@@ -53,7 +51,10 @@ func NewUnboundedExecutor() *UnboundedExecutor {
 // Go starts a new goroutine and tracks its lifecycle.
 // Panic will be recovered and logged automatically, except for StopSignal
 func (executor *UnboundedExecutor) Go(handler func(ctx context.Context)) {
-	_, file, line, _ := runtime.Caller(1)
+	pc := reflect.ValueOf(handler).Pointer()
+	f := runtime.FuncForPC(pc)
+	funcName := f.Name()
+	file, line := f.FileLine(pc)
 	executor.activeGoroutinesMutex.Lock()
 	defer executor.activeGoroutinesMutex.Unlock()
 	startFrom := fmt.Sprintf("%s:%d", file, line)
@@ -62,7 +63,11 @@ func (executor *UnboundedExecutor) Go(handler func(ctx context.Context)) {
 		defer func() {
 			recovered := recover()
 			if recovered != nil && recovered != StopSignal {
-				HandlePanic(recovered, file, line)
+				if executor.HandlePanic == nil {
+					HandlePanic(recovered, file, line, funcName)
+				} else {
+					executor.HandlePanic(recovered, file, line, funcName)
+				}
 			}
 			executor.activeGoroutinesMutex.Lock()
 			defer executor.activeGoroutinesMutex.Unlock()
@@ -105,7 +110,7 @@ func (executor *UnboundedExecutor) checkGoroutines() bool {
 	defer executor.activeGoroutinesMutex.Unlock()
 	for startFrom, count := range executor.activeGoroutines {
 		if count > 0 {
-			LogInfo("event!unbounded_executor.still waiting goroutines to quit",
+			InfoLogger.Println("event!unbounded_executor.still waiting goroutines to quit",
 				"startFrom", startFrom,
 				"count", count)
 			return false

unbounded_executor_test.go

@@ -39,13 +39,16 @@ func ExampleUnboundedExecutor_StopAndWaitForever() {
 }
 
 func ExampleUnboundedExecutor_Go_panic() {
-	concurrent.HandlePanic = func(recovered interface{}, file string, line int) {
-		fmt.Println("panic logged")
+	concurrent.HandlePanic = func(recovered interface{}, file string, line int, funcName string) {
+		fmt.Println(funcName)
 	}
 	executor := concurrent.NewUnboundedExecutor()
-	executor.Go(func(ctx context.Context) {
-		panic("!!!")
-	})
+	executor.Go(willPanic)
 	time.Sleep(time.Second)
-	// output: panic logged
+	// output:
+	// github.com/modern-go/concurrent_test.willPanic
+}
+
+func willPanic(ctx context.Context) {
+	panic("!!!")
 }